FAQs about Ultraviolet Sterilizers 2 Related Articles: Ultraviolet Sterilizers, Physical Filtration, Ultraviolet Sterilizers in Pond Filtration Related FAQs: Ultraviolet Sterilizers 1,  Ultraviolet Sterilizers 3, UV Use in Business Set-Ups, Rationale/Use, Selection, DIY, Installation Issues, Operation/Maintenance, UV Lamp Replacement, Repair

Ozone Output From UV Sterilizer 10/09/05 The most common opening line! You have a wonderful, wonderful site! And I mean it!  <<Thanks.>>  Anyways, I have purchased an AZoo 13W PL light UV Sterilizer for my 120G tank. I know these things are not 100% effective but can be helpful. Anyway, this sterilizer has an option wherein I can let air into it, something like the power head operated skimmers have. The box claims that after the air passes the PL lighting I will get O3 at the output. My questions are: How will O3 help in my FOWLR tank? Secondly should I connect the air intake or not?  <<Please read up on the ozone so you can determine whether you need/want to run ozone and if so, whether a UV sterilizer is the best way for you to do so.>>  If yes I don't have anything to regulate it other than the normal valve we use for air pumps? <<Ozone should not be added without some way to monitor it's affects and regulate. Ozone can harm your livestock and damage some components. Consult the manufacturer for their recommendations. In my opinion, if you determine that you want to run ozone, you are better off running an ozone generator and regulating the ozone with a controller. Again, there is lots of information on this topic on WWM.>> Thanks in advance. Keep Rocking <<You're welcome and good luck - Ted>>

UV recommendations 12/27/04 Hi, this is Jonathan. I have recently purchased a UV Sterilizer for my 125gal tank. I have been getting a lot of opinions about if UV kills or does not kill all the needed algae and beneficial bacteria. <UV kills whatever passes by it.  The rate of kill depends on the wattage and age of the lamp, the water flow through the unit, how clean the unit is, the specific organism in question and more.  Some beneficial life will be killed, but since most of the "good guys" are most abundant on surfaces, the UV will not make a significant dent in their populations.> I was just wondering because my tank is still developing, and I would still like to get some more hair algae and have for when I get a Hippo Tang. I also was wondering if that it's not so much the wattage but how fast or slow the water moves through the UV. <Hippo tangs are among the least herbivorous tangs and will eat very little hair algae.  The kill rate through a UV is dependent on both flow rate and wattage.  At very slow flow rates, even a small unit will have a high kill rate, but so little water will be processed that the unit will be ineffective.  The other extreme is a high wattage unit with very high water flow.... lots of water will be processed, but the organisms will pass by so quickly that the kill rate will be too low to be effective.  Hope this helps.  AdamC.>

Chillers and UV Hi, I've read for hours/days/weeks.  Learned MUCH!  I am setting up a 300 gallon Reef (96 x 24 x 30). Sump is fed by two 2" drains from overflows on each end. Sump also feeds a refugium which feeds back into the sump. Return from sump to tank is Velocity T-4 @ 1250gph @ 4' head.  The tank also is plumbed with a 1" bulkhead for a closed loop system that returns to the tank via a manifold around the top with multiple outlets. The question is regarding this closed loop system. I want to run my 1/2 HP chiller (I live in Florida) and 80W UV filter on this closed loop. Is there any reason why I can't do this? The UV filter is 2" in diameter and the Chiller is 1.5" in diameter. As long as my pump is rated to take the extra head, then why not?? <It would be fine but I would add a mechanical filter to the inlet of the U.V. and then plumb the chiller next.  The idea is that you do not want detritus to pass through the U.V.  It makes it less efficient.> (pump planned for this is Blue Line 70HD @ 1750 gph @ 4 feet, more like 1500 gph with the extra head caused by the UV and Chiller and the necessary plumbing). Also note that both the chiller and UV are rated to take this much flow, so that is not an issue. My concerns are that if I run the chiller and UV off of the sump then I'll be taking away from the already "low" return from the sump.  Heck, I've seen the inside of the chiller...its just a 4" diameter PVC pipe with a cooling coil inside...so I don't think that some circulating detritus could hurt it... Finally, can the 1" bulkhead support a closed loop flow of 1500 gph? <1" bulk heads can handle comfortably 700 gph I would recommend something larger.  The detritus will make the chiller and U.V. work less efficiently.  If you add a mechanical filter before U.V. and chiller then you should be fine.> Thanks!! Jim <Good Luck. MikeB.> Using UV for quarantine Hi!! I tried to use a different approach to quarantine for my new fish additions. I set up a 5 gallons QT with a huge Eheim canister with plenty of bio-media, carbon, Chemipure and nitrate remover so I can keep the water quality at its best. << 5 gallons is pretty small. >> It really works perfect, even with such a heavy bioload as two very small ocellaris, a Salarias fasciatus, a small blue Chromis and a 2 inches Zebrasoma flavescent. Also I kept about 3 pounds of live rock with some Actinodiscus. For keeping parasites and bacteria in check, I installed the biggest UV sterilizer I could find: a 24 inches, 36 watt one running 250 gallons per hour irradiating 90.000 uw sec/cm2, what is twice the required for killing the ich swimming larvae. You see, nearly every minute a volume of water equal to the whole system (11 gallons) pass through the UV. I expected this overkill method would be enough to exterminate this nasty disease without the need of chemicals but... NO! Doesn't work. Even adding a pump so all the water goes to UV every 30 second still the ich has time to find a host INSIDE the aquarium. I had to go back to the copper, something that I don't like at all because the brand that I use (Sea Cure) make my fish to look miserable and I always have to take some losses no matter how carefully I monitor the concentration. I don't know if there is any flaw in my idea, but I wanted to share my experience with it. << Thanks for sharing, I'm sure it will help others. >> Thanks you all for your wonderful and generous work. << Thinking the UV may still be a good idea, it just may need other treatments to go along with it. >> Cheers! <<  Blundell  >>

UV Sterilizer (10/31/04) I am told I should get a Coralife Turbo-Twist? What is it and why should I need it? <I'm going to assume we're talking about saltwater aquariums here, not FW or a pond. It is a brand of UV sterilizer. I am very satisfied with mine. Others of the crew do not believe in UV sterilization, and it is not without cons as well as pros. The concept is that it kills microorganisms in the water (both bad ones and good ones, of course). It may aid in prevention of bacterial and fungal infections and parasitic infestations (e.g.) ich, as well as the spread of algae spores. I'd suggest you read the FAQs regarding UV. There is also an excellent little piece about it in the article on marine parasites by Scott W. Michael in last year's Aquarium USA annual (The 2004 one, which may still be available somewhere, though the 2005 has been out for a couple of months.) Then you can decide if you really "need" (want) one.> Robert M. Levy <Hope this helps, Steve Allen.> UV electrical issue Hello Bob, <Rick> Your website has been a great help over the years.  However, I was unable to find anything regarding my current problem.  I am sure that you can help... so here it goes. Got a Coralife 9W U.V sterilizer that the bulb burned out after only four months of use.  No problem I thought.  So I replaced the bulb and now this new bulb only lasted two weeks.  I checked the UV casing to make sure that no water was somehow or another getting inside.  It checked out okay.  So I am faced with either electrical problems or possibly a bad ballast? <Yes. Next most likely cause... then a short, break in the wiring somewhere...> Have you heard of this issue before? <Yes, happens... particularly certain brands... Rainbow-Lifegard (now Pentair) had some real doozies back when... and most of the small UV's have much more trouble than larger wattages> I wanted to check with your advice before I dive into pulling apart the ballast and electrical assembly. <Mmm, I would NOT do this. Send the whole unit back to... likely ESU... check with your dealer/source first to see if they'll handle the return... most States have a pretty much carte-blanche warranty of one year... I would NOT fool with the unit myself. If you have troubles locating Energy Savers, or receiving authorization for return/repair/replacement, please make this known to me. Bob Fenner> Not much of a handy man but it appears to not be so difficult!   Any advice would be more than helpful. Thanks, Rick

Re: UV bulb electrical issue Hello Bob, <Rick> I took your advice and tried to contact my dealer (from eBay) about the UV electrical issue.  To my misfortune, this seller store is no longer available.  So I went to my LFS (dealer) to see if they would honor any "manufacturer warranty" only to find out that without THEIR store receipt I was basically up a creek with my paddle. Can you direct me to an ESU that you earlier advised as an avenue for repair? <Yes. Go to the source: http://www.esuweb.com/products/16Coralife_U.V._Sterilizers_Turbo-Twist_3x,_6x,_and_12x_TURBO-TWIST_3X_-_9_WATT_U.V._STERILIZER_-_UP_TO_125_GALLONS.htm see the contact info.? Call them. Bob Fenner> Paddleless, Rick

Re: UV bulb electrical issue Hello Bob, <Rick> As you requested, here's an update to my UV ballast burn-out and if problem was resolved by ESU manufacturer. <Good> I contacted ESU and advised them of my problem.  It took a couple of calls before anyone responded back.  Then I was promised that a new ballast for the Coralife 9 watt would be shipped out to me immediately. Well its been 6 weeks and nothing has been resolved.  No new ballast ever received!  Bummer! <Argghhh> In my wait for a replacement, I came across the ECO-Aqualizer.  I really liked the ideal of nothing to break-down nor need replacing and its money back guarantee.  So I decided to try one out.  I'm so glad I did. This thing is great.  Within a day, my water had a super polish look and my fish are much more active.  Its only been up and running for about a month, but so far the algae on my glass has needed less wiping and my water is still incredibly crystal clear. And I can't get over the added liveliness of my fish.  They look 100% better than ever, especially my powder-blue tang. <Wow!> I have decided to not worry about the UV sterilizer.  From the looks of things, I won't ever need it anymore.  But I do appreciate your help in trying to resolve that problem.  In a strange way, I'm kind of glad it all happened the way it did, otherwise I may not have ever even tried the ECO-Aqualizer.   Thanks much, Rick Johnston   <Thank you for your input. Bob Fenner>

Goldfish. Hi, <Hey Travel, MacL here with you tonight.> I have two questions... I saw on a website ( http://www.aquadirect.com/catalog/uv/customsealife.htm) a U2 Double Pass UV sterilizer.  I thought CSL (CustomSeaLife) went bankrupt earlier this year?  Are they back in business and operating under a new name? <I believe that while they have gone out of business they is still stock being sold under there name that was made previously. Least that my best guess.> I see the name "Clear Solutions" now is on the pictures?  This sterilizer looks very similar, however different. <Never heard of it but lots do come and go> Second question.  I have a 65 gallon tank with 7 goldfish.  They did fine the past 2 years... 2 weeks ago they suddenly started to go crazy (move like rockets in the tank, bump in the glass, in each other, etc.) when I turn on the lamp/light. <Anyway there is a short in your tank from the lamp> They do fine when the light is not on, they swim around happily, however once I turn on the light all hell breaks loose?  any idea why? What can I do to stop them? <Almost sounds like they are being blinded or shocked in some way.> It appears 1 or 2 of the fish start each time and the others just follow? Thanks for your assistance. Kind Regards, Travel CSL demise issues? Bob: <Steve> I thought you might find this incident interesting, if not a bit scary. You may recall that we speculated while I was in HI (still enjoying the memories, BTW) about the causes of the demise of Custom SeaLife. You mentioned some fire liability issues. Over the months, others have mentioned rumors of lawsuits. <Yes> I had a CSL Double Helix UV that I bought a couple of months before their demise. One day a few months back, I noticed that the light was not on (there's a viewing port). I disconnected the unit, unplugged it and tucked it away in a corner. Recently, I decided to get a new bulb. Well, when I opened the unit, I was shocked to see that water had leaked out of the tube onto the circuitry. There was corrosion and actual thermal burns! Thank God it didn't burn my house down. The thing I can't figure out is why it did not trip my GFCI. Perhaps all owners of this unit should inspect theirs carefully for evidence of internal leakage. <Yeeikes! There is an issue of a secondary "loop" circuit in many wiring arrangements of fluorescent lighting... that can bypass the GFCI circuitry/shutoff> I hope you are well. I regret being unable to afford ($ and time -- busy month including business trip to Madison) to come to MACNA, but look forward to an opportunity to get together again. Steve Allen <Indeed. Steve, do try to come out, enjoy Hawaii with your family. I don't have to be there! Bob F> - Flow Rates - Hi, I need some advice please. I have a 700 liter tank and 100l sump with a wet/dry trickle filter. The total head is about 1600mm. I have a pump with a 2500l flow rate. The curve on the pump shows that at head of 1600mm the flow is about 1500l. Is this sufficient? <It could be better.> What is the recommended flow rate? <Ideally, your total flow rate in a marine system should be at least 10 times the system volume. This can be accomplished with the return pump as well as circulation pumps [powerheads] inside the tank.> I also have an 8W UV sterilizer that I want to connect in the line to the sump. What is the recommended flow rate for that size U.V? <Well... for this UV unit, you'd want to give it its own dedicated pump, and not plumb it inline with your return. For the flow rate, it depends on what you're trying to kill. To kill the typical protozoan parasite, you're probably looking at about 180 LPH.> Thanks <Cheers, J -- >

UV Sterilizers 7/28/04  Hi--<Hey Janet, MacL here with you tonight>I read your article on UV Sterilizers and still have a few more questions. We have a 175 gal tank with 350lbs of live rock and the following: two false clown perculas, 1 coral beauty, 1 marine Betta, 1 strawberry Pseudochromis, 1 royal Gramma, 1 mandarin dragonet, 1 yellow tang, 1 Bannerfish, 1 harlequin Sweetlips, and 2 female blue devil damsels. I also have a cleaner shrimp and various crabs for clean up. I want to add a hippo tang, since my kids are so keen on having "Dory" from the Nemo movie. I know they are prone to ick, and the other day at a fish dealer I ran into a man who runs a business maintaining saltwater aquariums. He strongly recommends a 5 - 7Watt UV Sterilizer, especially if I'm going to get a Hippo Tang.<Actually in my experience I would add more cleaner shrimps and that should take care of the problem with ich.>  Will this kill off the pods in the tank and do you think it's a good idea? <What a UV kills depends on the speed of the water going through the UV filter. Whether it be algae or bacteria, etc.> If so, how often should it be running? Speaking of ick, I see one white speck on the strawberry. I can't tell if it's ick or not, because there are small white particles swirling around the tank, at least some of which look like pods. It's hard to tell because the power heads keep the water moving. Should I attempt to catch the strawberry and toss him in the QT? <If you only see one dot then just keep a close eye on him. The cleaner shrimp should take care of it. Cleaners are marvelous creatures.>  I hate to stress the whole tank if it's just a speck, and not ick. I've had a false alarm before. Would a UV sterilizer kill and ick in the tank? <Depending on the speed of water going through it, it will kill ich.> Thanks, as always! R/Janet

- Trigger Ich - Thanks again for your previous response. I check my water quality on a regular basis and it always measures out fine. However my fish keep getting ich. I was told that dropping the salinity down to 1.014 the fish would still live but ich cannot. <This combined with other treatments can help.> I have tried it for about a week now and they are still scratching. I only have two medium sized triggerfish in a large tank. Do you have any suggestions? <Might consider catching them and putting them through a pH and temperature adjusted freshwater dip... and perhaps even leaving them in quarantine for a while and running the tank fallow for six weeks or so.> The tank has been set up for about 2 months now. <That's actually not very long... could be you are having water quality issues which cannot be measured... would step up the water changes and get some other options up and working... for instance quarantine tanks.> What are your thoughts on a U/V sterilizer? <These provide some amount of good, but are not instantaneous cures and typically need low flow rates to actually kill protozoans - slow enough that the sterilizer will take weeks to see all the water in the tank. So yes, it will do you no harm, but no, it probably won't help in the immediate term. Please read here: http://www.wetwebmedia.com/parasiti.htm Cheers, J -- >

TMC UV flow rate hey <Isn't that for horses?> I read on the site that you guys highly recommend TMC U.V sterilizers. I just ordered a 110w commercial TMC model for my 220g fish only and am wondering what flow rate I should use it at? their website was a little vague for me to understand.  anyway I have a main system pump for my skimmer and sump that pushes about 800-900gph and I thought about just hooking it inline with that before returning back to my tank. thanks Brandon here it is: tmc-ltd.co.uk/filtration/uv_filt/TMCster_details.asp <Mmm, there are practical limitations... physical in terms of how much water one can push through such devices, and practical ones in the way of consideration of "kill rates" per pass... but somewhere around a hundred to two hundred gallons of actual flow per hour is about what you want here. Diverting the flow for other purposes is counter-productive (and intuitive). Bob Fenner>

TMC UV flow rate follow-up thanks for the reply but I hope you're mistaken. a 110w TMC U.V sterilizer and only 100-200gph. I hope not. here's another site that sells them: http://www.aquaticeco.com/index.cfm/fuseaction/product.detail/iid/8998/cid/2204 http://www.tmc-ltd.co.uk/filtration/uv_filt/TMC_sterilisers.asp tell me what you think. please. and thanks. <Mmm, I HAVE told/written what I think... let's see if it can re-stated in a different manner to relate the information. Yes, you can push water through this unit at the specified maximum flow rate of "Up to 17 GPM"... but you will not gain much in your setting... in terms of "free floating" microbe, algae population decrease, enhanced DO, Redox... all that you might gain by using such a unit... AND instead, being able to divert some of the flow that otherwise might be directed/diverted through the UV, running this about your system for added aeration, circulation is a better use. Think of this possibility (using a UV, having so much pumping capacity) as one of a few possibilities... not just how much water can be run through the unit. Bob Fenner>

UV and a refugium Hello WWM. I love your site! my question is simple (or at least short) I bought a U.V sterilizer and I'm using a refugium. Should I use the U.V or not. My tank is cycling. My refugium is full of life tons of Caulerpa and millions of copepods. The U.V defeats the refugium right? Thanks for all the info ..Bill <Actually, the UV and refugium are not mutually exclusive and ultraviolet use should have no discernible negative impact on the refugium. Bob Fenner>

Re: UV and a refugium Thank You! For the response  . That is very cool of you and I feel privileged to receive such valuable information from such experts. let me ask one more. First of all the stats: I have a 90 gallon. drilled tank with a 30 gal (I think, its big) refugium in the basement. I pump it back with a velocity t4 with about 8' head room into a SCWD which splits the flow back and forth from the rear corners at 45s. EV 150 skimmer. a 1/5hp chiller and the 25 watt U.V unit and two Hagen 4000 powerheads (should be enough flow)  Lighting 2 175 MH and 2 110w actinics. ( I'm shooting for the SPS / LPS tank) I looped the skimmer and the chiller and the U.V together. and 90 lbs of Walt smith's Pukani rock (thanks for the advice. it's the nicest rock I have ever seen) soooo my question is on the U.V ,should I leave it all the time or put a timer on it? Does it help the tank cycle? <I would leave the UV on continuously AFTER the tank has cycled> I'm afraid  of it's what it maybe killing good and bad. What do you think? Thank you Bob. I just ordered your  book. ( I cant wait) Your Friend Bill <Know you will enjoy, gain by its reading. Bob Fenner>

CSL Sterilizer and marine stocking Hi.  I sent this message earlier but didn't get a reply or see it in the daily FAQs. I suspect it didn't make it to you.  Sorry if you end up with two very similar sounding emails! Hello WWM crew, I have a CSL 18W Double Helix UV that has gone bad.  I have been happy with its performance and would like to repair it.  Problem is, since the company has gone under, I have no source for parts or info.  Apparently some water got into the ballast assembly and corroded the leads off.  An easy enough repair job.  However, there is a small component which looks like a type of bi-metallic over temp protector (but unlike any I have ever seen) built into a small bulb.  I have done several searches using everything I can think of and have come up with nothing.  There is no part number or *any* marking of any kind on the device.  Do you know of someone I could contact, possibly an ex-employee of CSL or someone who has ran into the same problem for information on this part? <Mmm, is still here... being re/circulated amongst folks in hopes that someone will have a more definitive answer. I would contact Perry Tishgart of Champion Lighting re... as he has boldly stated his company's former CSL inventory and intent to service their customers.> Also, I have recently set up a 72 gal Oceanic bow front that is the home of a porcupine puffer and a red Volitans.  I later learned from FAQs on your site (AWESOME!) that this tank is too small for the puffer and possibly even for the lion.  I am curious as to why since although both will get quite large, neither do a lot of swimming.  They are both lazy and are either hanging out in their caves, begging for food, or fluttering aimlessly around.  Is it a question of filtration or merely confinement? <A bit of both... physiologically and psychological> It seems like the bowfront would give a more open feeling  and allow them to turn around comfortably, etc.  If it is impossible to keep them, at what point (in inches) should I start thinking about relocation? Thanks for the great site and information. Kirk <At a year to three likely... but by then I strongly suspect you'll have "graduated" to more reef type interests! Bob Fenner>

Re: salinity  Dear Bob,  <James>  Thank you for your very quick reply, you are definitely not running on African time. I will keep my salinity at 1.025 as per your advice. I have also ordered your 1st book to keep me right.   <Know you will enjoy, gain by its perusal>  I have a quick question on U.V filters. Do I run it from a powerhead with a slow flow rate or through my Fluval filter which is much faster?  <There are "ideal flow rates", that is, calculated gph for achieving maximal kill ratios in a given volume... but practically speaking about the most flow you can get through a given unit, the plumbing achieves the most. I would use the canister filter discharge. Bob Fenner>  Kind Regards, James Barlcay

UV sterilizers Hi, <Hey there> Need some advice (thanks in advanced). Btw, if you can remember me, I'm the one that seeking your advice about the "free" Snow Flake Eel that come with the live rock. Well, FYI, I manage to trap it and now its at a diff. tank (living happily - I guess). <Ah, good> a) Can I turn on my UV sterilizers for long-term. My tank is with Coral & fishes? (My friend told me that the coral might not "open" anymore because the water quality change --- friendly microbes also get killed) <Should be left on continuously. No worries re killing off too much of the beneficial water-borne microbes> b) If can not turn on for long period, what is the recommendation? <Leave it on> c) I'm suffering for white spot 2 months ago. Most of my fishes died. left only a cleaner shrimp, 4 small fishes. I try to perform a "fallow" but couldn't catch the fishes, however after 6 weeks when I see no sign of white spot I then introduce 1 African Crown, 4 Common Crown, and 2 weeks later all dies due to white spot. Must I remove all fishes? <Yes my friend> d) If I manage to catch all the fishes, Can I leave the cleaner shrimp inside while performing the "fallow"? <Yes> e) Due to the white spot, I purchase a 9W UV Sterilizer. Will this be the BEST solution (against white spot) for me to always turn it on? and perhaps couple with a "quarantine tank system" for new fishes? Or the UV system is already enough? <Quarantine... and possibly dip ALL new fishes. The UV alone will NOT prevent or cure Crypt infestations. Bob Fenner> thanks.  rgds, ws teoh

Re: UV sterilizers Hi Bob,    Thanks for the response.    btw, as for now I just manage to "trap" 1 of the 4 fishes. hope to trap the other 3.    thanks. rgds, ws teoh <Good luck my friend. You may have to drain the tank down to give you the advantage. Bob Fenner> UV sterilizer Will a U/V sterilizer help destroy red slime algae since it is a bacteria?<It may help a little but the best thing you could do is get a good quality protein skimmer and keep up on the water changes using RO water.  If you don't already have a UV I would not purchase one for your uses.  Cody> Thanks!

75 Gallon Stocking II Hey again,<Howdy!> I forgot to mention about the tang the ich thing won't be a prob.  I've got a UV.  <UVs are no guarantee against ick, it only is effective when the ick is actually in the water column, which is not for very long.  I would set up a quarantine tank now as they are one of the most important components to being successful.>Is this still a no go due to size?<Yes, they are also very touchy fish.  You can read up about all this some more at our website: www.wetwebmedia.com.  Cody> Akira

UV Questions <Hello! Ryan Bowen with you today> As always, the information on your site is very informative, however I was not able to find an answer to my question this time! <No problem> I know bigger is better, and I have two marine tanks side by side and the water runs between the two tanks (a 110gal and a 55 gal). <Cool> I have two water pumps, that circulate the water back and forth. (Stocking is mild I would think... (Please give your opinion) 110 gal holds; 1 large maroon clown and a med. Atlantic anemone, a med/large finger coral, one electric blue and yellow damsel, one Chromis, 2 cleaner shrimp, one boxing shrimp, 6 turbo snails, 1 brittle star fish, a good size angel (not sure what type, but she eats well and is healthy) and a yellow tang. <Everything sounds good, although the angel could certainly need bigger quarters, depending on type.>  There is about 1 inch of sand on the bottom and about 50-60lbs of L/R with an under gravel filter that runs, not a plenum (sp?), two power heads to run the U/G, a Fluval 304, the custom built-in filter (made for the tank), a SeaClone 150, and a double helix UV filter rated for 150gal. <OK> The  55gal houses a mated pair of Percula clowns, 3 Anthias, 2 3-stripe humbug damsels, 5 hermit crabs, and 5 clear shrimp (they are feeder shrimp who never got eaten! They are now too big to eat but do a good job cleaning, so I left them in.) There is also a Fluval 304 on this tank, a Berlin air-lift 60, an off brand UV filter rated for 100 gal tanks, 2 power heads and an U/G filter. 2in. of sand and about 30lbs L/R. Water parameters are PH-8.2 ammonia-0 nitrites-0 nitrate-0? (test is hard to read the difference between 5 and 0 at least under 5ppmcalcium is 405.) ***My question is this... I have a 25gal bare bottom tank with an Aquapro-1 filter (-British brand? rated for tanks up to 50 gal)<Never heard of it> that I use for my QT tank. When there is no fish living in it, it is connected with the main tanks to help with circulation (so the good bacteria don't die in the filter).<Nice setup> When there is a fish inside, I take off the connecting water pumps. I was wondering if I could keep the quarantine tank in connection with the other tanks if I placed a UV filter between the QT and the 55 gal. when there *IS* a fish in the QT, and only disconnect them should the need arise for medication? Thank you for your time and sorry it took a lot to get the question out! Amanda <Amanda, it seems pretty risky.  The entire idea of a quarantine system is to prevent any possibility that contaminants can proliferate in the display.  If copper medication would ever need to be used, you would not be able to reconnect the QT tank for fear of copper poisoning your invertebrates with leaching.  Good luck! Ryan> - UV Sterilizer Questions - Hey folks, Hope all is well in WetWebMediaLand. <As far as I know.> I need some clarification (har!) on UV Sterilizers. <Ahh... good one.> There seems to be a lot of difference of opinion regarding their use. I've poured over all the information on UV sterilizers on all the various reef-centric boards with regards to their effectiveness on Cryptocaryon irritans (Ich) control in the free-swimming stage. One thing I never saw addressed was "sizing big" when purchasing a UV sterilizer. It seems that a 50 gal aquarium calls for an 8 or 9 watt UV sterilizer. Many people claim you will have better parasite control with UV if you restrict the flow to 50GPH through the unit. While this seems to make sense, I'm wondering if "upsizing" your UV sterilizer would have a similar effect rather than restricting water flow. The difference in cost between a 9 watt and 15 watt is minimal, and the cost to move up to a 25w seems reasonable. <It might 'seem' reasonable, but you should know that a 25 watt UV still needs a flow rate of about 150 GPH to kill protozoans. There is no exponential relationship between the size of the UV and the required flow rate.> I currently run a closed-loop system with a SCWD and Mag unit that's rated at 700GPH. The loop is simple in my 37 gallon Oceanic "Cube". It's basically a Lee siphon tube running to the Mag, then from the Mag to the SCWD, then the SCWD to the outlets. I assume that the flow gets restricted significantly right at the SCWD, particularly when switching. <Actually, no... this item is well engineered and causes no back pressure when switching.> I'm considering picking up a 15w AquaUV unit to place between the Mag and SCWD. Is this the optimal spot? <No. The ideal way is to plumb the sterilizer separately with a dedicated pump in the sump and a return line to the tank.> If restricting the flow through the UV unit makes for a tangible benefit, should I isolate the UV unit with a couple of T barbs and restrict its flow with a ball valve? <This would also work.> Thanks so much for your help. Karl <Cheers, J -- >

- Ultra-Violet Filter Flow Rate - I have a 270 gallon tank with  a 40watt Pentair u/v. Could you please tell me what the best flow rate for this u/v should be, and how often the bulb should be changed. <Hmm... proper flow rate will depend on what you want to kill with the UV. Would guess that a flow rate around 300 GPH will be sufficient to kill ich - would check with the manufacturer to make certain. As for bulb changes, once a year should be sufficient.> Thank you. Ned <Cheers, J -- >

UV for a Reef (12-15-03) Also, Is a UV beneficial or harmful to a reef environment? I have 57 Watt, and I'm thinking reef?<It's a matter of opinion here, some people run a U.V some don't.  I run a U.V on my reef and have seen no ill effects.  It seems to help with water clarity and algae outbreaks.  I say research and decide for yourself as each person views this in different ways.> Thanks for all your help!<My pleasure! Cody>

- UV Sterilizer and Other Questions - Hello WWM, First I would like to thank you so much for all of your hard work on the website. It is first class. I have two questions: <Ok.> I have a 230 gallon FOWLR Marine tank that's water parameters seem to be perfect.  NO ammonia, Nitrite in the last 9 months or so and my PH and DKH are always right on.  My frustration lies with my nitrates.  They have been creeping up lately and now are at 20ppm.  I just did a 55 gallon water change this weekend and it did not seem to help.  How often should I be changing my water and how much? <I like 10% every two weeks, but 5% every week is probably overall the best for any tank if you can stand that much maintenance.> And how would you recommend that I fix this nitrate problem quick? <Depends on your system... do you by any chance have a wet/dry filter?> Also what is an effective level for calcium? <In my opinion between 350 to 400 although many prefer 450ppm. Depends really on maintaining those levels.> I am trying to grow more purple algae. Secondly I have a double helix UV sterilizer (36 watt), in my sump.  Is that enough wattage and should I purchase another? <I don't think UV is worth the time or money on main systems - great for quarantine, but hard to tune for larger systems. The big variable is a low enough flow rate adequate to kill protozoans.> I also am curious if there is a place that I can put it to make sure it is most effective? <Again, careful quarantine procedures can make UV sterilization a waste of time, and likewise there is some anecdotal evidence of an acquired immune problems in systems that have run UV for extended [years] periods of time.> Your help would be greatly appreciated, Matt <Cheers, J -- >

Would You Use a U.V. for This? >To the Wizards of WWM, I love your website! So I thought I'd ask another question. I have a 75 gal tank that has been running for some years now. I've recently upgraded the lighting to a MH/PC combo.  I am now having a terrible problem with algae bloom, on the rocks, substrate and glass.  I never had this problem before with my previous lighting setup, (SO Fluorescents).  Yes, I also have a working skimmer.  I realize that it is probably too many nutrients in the water; even though the algae returns only 2 days after a major water change.  I got the idea to use a DSB with some LR in my sump to help cut down on the nutrients.   >>It's a pretty good idea.  Make it a full-blown refugium and you'll be even better off (for the use of macroalgae through which harvest would garner direct nutrient export). >However, the guy from my LFS, suggested a UV Sterilizer instead. >>Because a U.V. would do what, exactly? >HUH???? >>YEAH! >Should I use the sterilizer instead of the DSB? >>Um.. NO.  They don't have anything to do with each other, one sterilizes (this means kills things), the other GROWS things that utilize and convert certain nutrients. >Would both be effective? >>In their own capacity.. well yes, though I'm not at all a fan of U.V. in home aquaria, ESPECIALLY reef with refugia. >Please help. I'm just about at the end of my rope with this problem.  MiMi >>This guy is.. how do I put this..?  Talking out of the wrong orifice.  He clearly has NO IDEA what the function of a DSB is, nor the function of a U.V. sterilizer.  If there were a stupid law it would say that you may smack him upside the head simply for being so.  Let him not muddle your mind with useless drivel.  Marina

Ultraviolet Sterilizers? I have a 20 gallon long tank.  I want to add a UV sterilizer.  Could you recommend a good UV for this type of tank?  Or do I even need one?<To be honest with you...I would not purchase a UV sterilizer for an aquarium this small. I would make sure that you have a protein skimmer though. Good luck, IanB>

Shortest question of the week: UV use 10/18/03 How do you feel about the use of U.V sterilizer in 75 gallon tank. <ahhh... that depends if it is on freshwater, saltwater or a QT tank? Hmmm... frankly, if you are quarantining all new livestock properly in a QT tank (with UV if you like) before adding them to the display, the UV will not be needed. They are also strict in application (require maintenance of an excellent prefilter and the use of carbon and/or ozone weekly or better for water clarity). Anthony>

To UV Or Not? Hi Scott, how are you doing, hope you're doing great. <I'm doing great! Hope all is well with you...> I just purchase these weekend my protein skimmer, I got the REEF CS6-1 Series, and works like a beauty, but barely fit. <Hey- at least it fits! A great skimmer that will do a wonderful job!> Doing a little research, I wanted to ask your personal opinion on Ultra Violent Sterilizer, are they necessary, do they help a lot, or are only necessary for reef tanks????  Thank you for your advice. Att. Juan <Not necessary, but a nice thing to have. Personally, I think you can get by without UV, but it's your choice! Do some research on the WWM site regarding UV use in reef systems, and you'll be able to make an informed decision! Good luck! Regards, Scott F.>

- Effectiveness of UV Filtration - Are there any scientific data or real life experiences of effectiveness of UV lights in killing Cryptocaryon (marine Ich) spores (free swimming)? <Yes. It's all a factor of bulb wattage and flow rate.> I'm looking to get CSL Double Helix 36W for my 90 gallon. The flow through the sterilizer will be 200gph. Big question: will this dosage be enough to kill free swimming Crypto spores? <You need to ask Custom Sea Life - they should have data on the effectiveness of their bulbs vs. flow rate. They should be able to recommend the correct flow rate to kill protozoans.> Thank you,  Luke <Cheers, J -- >

- Water Flow, UV, and Plumbing - Hey! <Hello to you.> I need to increase the turnover in my tank and increase the efficiency of my UV. I have a 75g FOWLR, with built in overflow that goes down to a wet dry, in the wet dry (sump) I have the skimmer. I have a little giant pump rated at 590 gph w/ a 6' head, that also pushes water through a UV that is rated at 350 max outflow, the pump is connected to one end of the sump. What I figured is that I do not have enough turn over in my tank and that the flow is too strong for the UV to be effective. So what I want to do is to get another external pump rated at about 400gph including the 4-6' head to pull water out of the sump and connect this pump to the UV, my tank has one main hose that Tees off into two bulkheads, one on each of the corner of the tank, (the main is a 3/4" hose). 1. The only way that I can get this other pump to pull water from the sump is to have a hose or PVC tube and elbow go over the sump from the outside and down in the sump to pull water, my sump is about 14" high, then connect this one to the UV, would this work? <Only if you have a pump that can self-prime... and I can't think of any in that GPH range. Most pumps won't 'suck' water from any height and instead rely on being primed by gravity - via the bulkheads on the side of the sump.> I can't really drill another hole in the sump. Is there any other way of doing this? <I think you will need to find a way to drill the sump or put the pump in the sump.> 2. To get the water back in the tank I thought of joining the end tubes (one hose coming out of the outlet of one pump, and the other one after the UV from the other pump) into a Tee that will be connected to the main and then this will Tee into the two hoses that go to the bulk heads. Basically combining the outflows of two pumps (pushing up) into one main going up to the tank. This is the easiest option for me. <It's not the best option, however... better to have each flow into the tank individually.> The other option (but it's harder to get to) is to have each of the pumps connected to each of the bulkheads, through their own hose, no Tee. This will have different flows out of each bulkhead, I don't this is a problem, is it? <It's not a 'problem' per se, and it's preferable to combining both pumps to one.> Would this increase my turnover? <Yes, but you might want to examine your UV to see if moving water through it at its highest rated flow is in your best interest. For example, a 25 watt UV might be able to move 400 GPH of water through it, but if you want to kill protozoans [which is what I'm guessing you want to do] with the UV you need the water to sit in front of the bulb a little longer, which [again on a 25 watt bulb] means slowing the flow down to 150 GPH.> Any other suggestions? <Cheers, J -- >

Cleaning of U.V quartz sleeve I am using a 4 x 30 watt Aquanetics quartz sleeved pond U.V on a centralized store system.  I would like to know how often you would recommend cleaning out the unit and how I might best go about the process.  (I recently enjoyed seeing Mr. Calfo speak in Orlando...he was great!) <About once a month in the season when water is more than 65 F. is about right. Turn unit off (unplug), remove compression fittings and VERY carefully remove and wipe sleeves down with a paper towel (in tough cases with an alcohol as a solvent)... taking care NOT to touch the sleeves to anything hard (they will break... easily). Bob Fenner> thanks, Dave

Setting up a UV on a goldfish tank (07/26/03) Hey folks, a quick question or two.   <Ananda here tonight to give a shot at answering them....> I have six (I know, I know 5 is the magic number) fancy 4" goldies (really 2 Black Moors, 2 Red cap Orandas and 2 brassy Ryukins) in a 55 Gal. with a Eheim 2026 filter and a Coral Life 9 watt UV sterilizer. <Having read about how messy goldfish get, I'd consider an additional filter... that Eheim is going to turn your tank water over only about 5 times an hour. For my messy fish (puffers), I have the tank turnover at 12 times an hour, and I still have more nitrates than I'd like.> As a new setup the sterilizer is off.  My gravel substrate is cultured and the water conditions are 0 ammonia, 0 nitrite and a pH 7.8 (a little bit high) filter is still ramping up. <How are the nitrates doing?> The sterilizer is rated for a flow rate of 100 to 200 gph, slower being better.   <Yup.> The Eheim is rated at 250 gph but can be throttled back.   <I wouldn't.> My assumption is that the filter full of media and with a head of 34 inches plumbed to the UV then into the tank is developing something less than 200 gph.  A guess as to how much less?   <There are head pressure calculators around on the web... I don't have any canister filters, so I am not sure.> And should I throttle back to let the UV get the parasites?   <I would get a dedicated powerhead for the UV.> Thanks, Rick <You're welcome. --Ananda>

Putting UV To Work Question about Ich... Do UV filters help in the control/spread of Ich and other pathogens in the water? I heard they do, but just want to know before spending $100 on one of these babies. Thanks much, you guys are great!! <Well, there are some serious benefits to using UV on a continuous basis in your system. They do kill many free-swimming pathogens, among other things. It's possible that they can kill the Cryptocaryon parasite during the free-swimming phase of its life cycle. The key to success with UV is to get one of the proper size for your system, and to run the proper flow rate through the unit to achieve an effective contact time to take advantage of the sterilizer. Good luck with your system! Regards, Scott F>

Calcium reactor, UV, Ozone Hi again, <Hello to you, JasonC here...> I have a simple one this time. I am constructing a FOWLR. Will this benefit from having a calcium reactor? <Not especially.> Will the presence of calcium help me grow a more diverse range of "things" on the live rock or in the sand (I plan to have a deep sand bed too). <It would pay to keep the calcium in a decent range, but you could achieve that with additives. Calcium reactors become more useful when you have organisms that consume large amounts of calcium.> Will a UV sterilizer help or hinder a DSB and LR? <Don't think it will affect it either way, but in general more useful for hospital and quarantine tanks.> I want to use ozone, how do I know what size of unit to buy? <Buy what you can afford WITH the controller.> I cant find much on that. I plan to use an ORP controller so that will take care of things for me but I don't want to buy a unit that is too big or small. <Most of the small units available to aquarists are too small to get into big trouble with.> Thanks, Adam L <Cheers, J -- >

UV effects on plankton? 5/20/03 Good morning everyone!! <cheers> I have heard that if you have corals in your aquarium, you shouldn't use a UV sterilizer, because that would eliminate the things that the corals feed on.  Is this a fact???     <a small matter either way. Assuming your tank even produces plankton (few do adequately to feed corals).. the UV will nuke some plankters... yet the dead are still consumed by filter-feeders. Ultimately, though... I see little need for a UV on a display tank... a poor method of disease control (dubious efficacy under practical applications). Ozone would be much better for this purpose and has other benefits> If this is true, then if I were to use a UV sterilizer, and manually feed phytoplankton a couple times a week, would the corals be satisfied??    <agreed> I ask this because I have noticed that UV sterilizers help control unwanted algae. <they certainly do... and very well. Yet, the cause of the algae is excess nutrients. Control the nutrients (aggressive skimming, proper feeding/stocking and water changes, etc), and the UV is still not needed> Pat Marren <kind regards, Anthony>

- Running UV - Hello, I'm running a 40W UV. sterilizer (750-800gph) and would like to add another. My question: Is installing the second one in parallel or series going to be more efficient? Regards, Kevin Pockell <Well, Kevin, for starters... that flow rate through a single 40 watt UV isn't going to do you a whole lot of good, mostly because the contact time between the UV light and the water is too brief. To kill protozoans [Ich and the like] with a 40 watt UV, you need a flow rate closer to 350-375 GPH. So... would two in a row be more efficient? I don't think so, you'd do better to put the UV on it's own circulation loop, fed from the sump and out flowing directly into the tank - this would give you easier maintenance on the UV and more efficient use of the unit you have. Cheers, J -- >

Benefits of UV Sterilizers I have a 55 gallon. Are UV Sterilizers worth the money? I found one on Dr. Foster and Smith for $74.99 Will it really cut down on disease and stress? One of my LFS told me to be careful of  “snake oil salesman” What are your thoughts? <In general, since I know nothing about the tank's livestock, yes UV sterilizers are beneficial. Worth the money? Too subjective for me to answer. If you keep a low bioload, properly QT new livestock, practice good husbandry, I would recommend you spend the money elsewhere. Hope this helps, Don> Thanks TGIF Christy

Should He UV? Good afternoon gentlemen, <A gentleman...Hmm- I'll have to think about that one...Scott F. with you today!> I'm TIRED of fish being lost do to not having a QT tank!!!! So I'm buying what's needed to do things RIGHT( like I should have done the first time) So my question is to you fine gentlemen: Should I dish out some more beans and buy a U.V light for some Extra caution? What do you think? THANKS for your time. <Well, UV is a useful tool in aquarium husbandry; it can kill free swimming pathogens if the proper flow rate through a correctly-sized unit is achieved. It's not mandatory in an aquarium, but it is a big help! On the other hand- there is really no substitute for good technique, such as quarantine. If you don't have one already, I'd invest in a simple quarantine tank setup (A 10 or 20 gallon tank, sponge filter/outside power filter, heater). It will more than pay for itself in the fishes that it saves! Then, if you feel that you need it- go for a UV sterilizer...Good luck! Regards, Scott F>

Any preferences or advices to choose between these sterilizers (9watt lamp) Coralife Turbo-Twist 3x <I see from your next email you made your decision> Custom Sealife U2 Custom Sealife Double Helix They all seem to have max aquarium size u to 125 gals and all claim to be the best :-)  <Very common in the world of advertising. I see many claims as to the best car, but as long as the mileage is decent, and it takes me reliably where I need to go... I personally don't use a sterilizer, and really don't see the need for one on my system, so I'm not up on their qualities. I would advise asking such a question on a forum, you can try ours over at http://wetwebfotos.com/talk/index.jsp someone there doubtless knows more about sterilizers than I do. > Thank you, Luke <Sorry I couldn't be of more help, have a good evening, PF>

UV light - good for flukes, Ich and velvet (marine tanks) <Hello again Luke>I have one 35 gallon tank (marine) and I'm planning on putting Coralife Turbo-Twist 3x UV sterilizer, which they say is good for up to 125 gallons. <Seems a bit of overkill on your size system> The flow through the sterilizer will be 150gph. I'm wondering, if at this dose will the UV light also kill flukes and marine Ich and Velvet? <Well, I haven't really heard that flukes are a common problem, such as ich and velvet are. As for them, yes the sterilizer will kill their larvae. But, that might not prevent an outbreak, or an ongoing infection. Such diseases have more do with a lack of proper quarantining and stressed animals due to poor conditions/overcrowding than anything else.> Thank you. <Your welcome, have a good evening Luke, PF>

UV connection I bought a Tetratec™ UV5 5 Watt Clarifier for the tank, I wanted to hook it up to the Fluval 404. Man did I have a hard time! The water kept leaking! I finally had to cut a piece of hose from the line I use to siphon the water out of the tank and two hose clamps and it's working. Just thought I'd share that with you in case anyone else has the same problems. So far so good, the three damsels that are left seem to be doing fine and I've noticed an improvement in the quality of the water already! <Plumbing can be a frustrating experience, eh? Thanks for the update and good to hear things are improving. Don>

Weird UV Question >Well, perhaps it is not so weird.  Hopefully it will help many. I have a Coralife Turbo-Twist 3X (9W) UV Sterilizer.  It uses a Philips PL-S 9W UV-C bulb (also has TUV on the box). Aquarium suppliers charge between $25 and $35 for replacement bulbs. I did a Google search on Philips pl-s 9W and found a supplier that sells them for $3.50 apiece!!!!! >>Egads! >But then I did more research.  Turns out Philips makes 5 versions, the only difference being the Kelvin rating (27K, 35K, 41K and 50K).  Nowhere on the bulb box, on the bulb, or in the Turbo-Twist documentation is there any mention of Kelvin rating. >>Not uncommon on bulbs not designed for such specific applications. >So the question -- does anyone know which version this unit uses, and does it matter (I presume it matters a lot but my physics is in my distant past!) >>BOY!  I sure don't, and I've never used a U.V. sterilizer, either.  I would contact the manufacturer to get specific information.  By doing that, you will satisfy one of two questions: 1)determining pertinent wavelength & manufacturer information or 2)determining why these bulbs may not be offered for sale or are otherwise unsuitable for this use.   >Thanks! If these bulbs are usable I'll be happy to send the link to the supplier!  Joel >>Please do let us know anything you find out.  More knowledge is definitely BETTER.  Good luck!  Marina Re: Weird UV Question >Well, two things happened between my note and your reply.  First, I contacted a bunch of folks as you suggested.  Second, I remembered my college physics (I started out in astrophysics before becoming an expert in Russian Politics).  The first proved useless for the most part.  Even the manufacturer had no answer.   >>Hrm. >But then my physics reminded me that these bulbs are emitting in the ultraviolet, not visible range.  So they will not have a Kelvin rating.  The bulbs mentioned in the post and that list for just a few dollars are in opaque (mostly) white tubes that filter out much of the UV light.  In a weird twist of capitalism, that SHOULD cost MORE, but they sell for a pittance. >>AHA!  That makes sense...and I'll just admit right here that I've had no such physics education.  I can tell you that the tubes used for U.V. bulbs are made of quartz, though.  IIRC!   >The bulbs in UV sterilizers, however, are in clear tubes and emit at wavelengths that make them germicidal, sterilization devices.  They are primarily used in the medical profession and in other select applications, such as ours.  This is what makes them cost more.  Other than the outer tubing, there is little that distinguishes the $35 from the $3.50.   >>Again, IIRC, U.V. wavelengths will be on the order of something like 400nm-320nm. >Fortunately, I did find a supplier that sells them for $15.  It is: http://www.worldwidespecialtylamp.com/phil3.asp >>Great! >Thanks, Joel >>Thank YOU, Joel.  Lots of folks will be happy to spend so much less on these bulbs.  Marina UV vs. Skimmer Dear Crew: What an awesome group of people and a terrific website!!!!!!!! The only downfall is you can find yourself at the computer screen for hours on end!!   Great reading.  Keep up the good work. Hoping you might answer whether I need any additional equipment. Current setup is a 150 gallon Marine Tank, 1 year old.  Fish Only. 1 Large Clown Trigger, 1 Picasso Trigger, 1 Blue Tang, 1 Sail fin Tang, 5 Yellow Tang, 1 Naso Tang, 1 Mexican Rainbow Wrasse, 12 Damsels, 2 Tomato Clowns.  All are doing very well.  Feeding Seaweed sheets, Brine Shrimp, Formula 2 and periodic Squid etc. The tank has numerous dead coral pieces.  I am cleaning the tank at least every 2-3 weeks due to the coral, powerheads, glass etc. building up with brown algae.  Bleaching and elbow grease always solves the problem.  Question?  Can the brown algae buildup be cut down with additional equipment such as a UV sterilizer or a protein skimmer?  The current equipment setup is:  @ wet/dry's (stand wouldn't accommodate one larger one) Three cabinet setup.  1 Wet/dry on each side.  2 Magnum 350's, 1 with pleated filter, 1 with carbon in the middle.  4 x-large powerheads in tank, 2 spread out on each back side of tank.  Circulation only w/ 1 bag of carbon in each powerhead strain canister.  Lot's and lot's of water movement.   After each cleaning within a day the tank is crystal clear but generally erodes within 3 weeks.  In addition to more frequent water changes (25%??)also how often? is their anyway of lowering the algae growth? PS: I have been using tap water with chlorine etc. remover.  How important is it that I start using Distilled water? Also, is there anyway of brighten up white coral?  Does it brighten more with bleach or sitting in the sun?   What is a good rule of thumb for bleaching and cleaning Dead Coral.  Thanks for any help you can provide!!  Lane   <Hey Lane, a good skimmer would definitely help in this situation, you have a heavily stocked tank and some messy fish, the skimmer will help to remove excess nutrients from the water.  Take a read over our skimmer section for more information.  The tap water could also be contributing to the algae problem, it may have a large amount of phosphates or other nutrients to help the algae grow.  Distilled water will cost you a bundle if you are doing 25% weekly water changes, you might consider looking into an RO, DI, or RO/DI unit.  I have heard good things about the Kati and Ani system from DrsFostersSmith.com. I have not had to do much coral bleaching, I'd say a good dose of bleach and water solution should take care of it, 1cup (straight bleach, no perfumes or dyes) per 5gal of water.  Maybe more bleach, be sure to give them a good rinse when done and let them dry in the sun to dissipate the bleach.  Best Regards, Gage>

UV vs. Skimmer Gage: <Hello Lane> A UV Sterilizer wouldn't be worth my time? <Not compared to a good skimmer, both would be nice, but if it were me I would save the money from the sterilizer and put it towards a better skimmer.  The better you skimmer is, the better your water quality will be, and the less things (algae, bacteria, parasites) you will need to zap with a U.V sterilizer. -Best Regards, Gage>

Inline UV Question Can I run an Eheim 2213 canister filter inline with my Aquanetics 8watt UV sterilizer?  This is for a 37 gallon fish only marine tank. <You can but it will affect flow rate some.  Craig>

UV/Protein Skimmer Once Again I am calling on your wonderful help. <Welcome back!> We purchased a UV Sterilizer for our 75 gallon soon to be reef.  Would it be ok to have the water that comes out of our protein skimmer be the water that enters the UV Sterilizer?  Both machines have the same pump. Thanks Annette <Do you mean a direct connection?  As long as both the skimmer and UV unit receive the correct flow rate and there isn't a bubble/air trap (from bubbles in the skimmer effluent) there is no problem. You might tee both off of the same pump, separately.  Craig>

UV sterilizer questions Hi! I've been reading your site (Q&As) with great interest! It's a great source of knowledge that you can combine and then use to make intelligent decisions on your own. Anyhow, I have a 130-gallon freshwater tank, with a Magnum 350, Aquaclear 300, and undergravel filters powered by three Hagen 402s. The output of the Magnum goes through a Tetra-Tec 5-watt UV unit (WAY too low, I know), then Tees off to send part back to the tank and part to two bio-wheels. I am considering getting rid of the Magnum (it's a maintenance pain) and replacing it with a second Aquaclear 300. I've also just purchased an 18-watt Custom Sealife double helix hang-on tank UV unit. My questions: 1) How is the Custom Sealife unit, and is 18-watts enough? <I would use the manufacturers size recommendation. If it is rated for at least 130 gallons, then it's likely fine. A filter you will maintain is better than one you won't.> 2) I am planning on powering it with one of the Hagen 402s (270 gph) which is sitting on top of my undergravel filter uplift tube. Is this OK? <If this matches the needed flow rate then it's okay.> 3) I am also planning on taking the output of the UV and running it over ONE BioWheel and back into the tank. Is THIS a good idea? <No matter, it will flow over the wheel one way or another, this doesn't improve or detract from anything.  Not really necessary.> Thanks so much for your help and keep the great site!!  Larry <Have fun Larry, follow the owner's manual and manufacturer's ratings. Craig>

Re: UV sterilizer questions Craig...you missed the first question... My questions: 1) How is the Custom Sealife unit, and is 18-watts enough? <Hi Larry, I answered part of it and intentionally didn't answer the other part! I don't use UV, but the main difference between most is marketing, not substance, especially in an aquarium with multiple passes and proper care/husbandry in all other matters, i.e.: quarantine, filtration, water changes, maintenance, and so on.  Too many hobbyists use a UV as a crutch in an attempt to overcome poor husbandry.  This is not what they are intended for. In a cursory search on Yahoo I found four or five sites carrying 15watt Coralife aquarium/pond UV units rated up to 300 gallons of aquarium. I didn't see any at 18 watts, although they may be available, as you mentioned you purchased one. The 15 watt units look fine to me and should work if they fit (plumb) in your set-up the way you intend. The answer is: use the manufacturers recommended size rating.   Hope this helps!  Craig> Re: UV sterilizer questions Craig...thanks for your response and to-the-point answer. The reason you couldn't find the UV unit is because it's a "Custom Sealife"...not Coralife. See it here:   " http://www.marineandreef.com/shoppro/sterilizers_Custom.htmlLarry <Thanks Larry!  Same answer different unit! They rate it conservatively at 100 gallons at this link. The inner sleeve sounds good as is easy bulb replacement. If it fits your system the way you intend it should work fine.  <Yours, Craig> Anthony, could you look over this email response and add insight. My Reponses are there already. Should I send the original to you for a second opinion and posting? What is the proper Wet Web protocol? Thanks. Paul

To UV, Or Not To UV? Thanks!  Regarding UV, by the way, I know you are supposed to turn it off when using meds.  When can you turn it back on?  Can you do a water change, replace carbon filter, and turn it on?  Or do you need to wait a while, and if so how long? <I'd turn it back on after the change, myself> Since I'm on the subject, what about when using plant fertilizers like Flourish, products like Melafix, etc.? <I would not be as concerned about the plant foods, but with medications, I'd refrain from the UV usage> Thanks! <My pleasure! Regards, Scott F>

- More Questions - I always thaw the food first. <Ahh, good.> I figured that frozen was not the way to go. It ate a good amount of plankton today. Hopefully this it will keep in. I have a PC dual light that is around 75 watts and another one on order. <You will likely need more light than this...> My tank is only a 30 gallon a and the Eheim is rated for 66 gallons. You don't think this is enough? <No, for effective UV it is probably too much - the trick is the amount of time the water stays exposed to the bulb... for a 25 watt UV, the approximate flow rate is 150 gallons per hour - for a lower wattage bulb, the exposure needs to be even more, so the flow rate should be even less.> Today the fish are looking real good. Possibly the best I have seen them yet. I thought that the only time you can kill it is when it is free swimming. <Nope, parasites are susceptible to treatment most any time.> Also my fish are not itching except very rarely and every spot clears up in about a day or so. <Again, these parasites are like creatures in a horror movie - they go away long enough to reproduce and then come back in ever larger numbers.> What if I was to add ozone to my protein skimmer? <Ozone would help, but this tank is small enough where you might do more harm than good - ozone is very reactive and easy to add to much to the point where it will affect your health too.> I will just take care of this the way you suggest but I really just don't want to set up a second tank quite yet. <Is your choice.> My fish while I like them are still cheaper ones because I did not want to go buy expensive fish right off the bat. <Well... I like to consider all life as precious, regardless of the arbitrary price other people put on it, but when you do consider more expensive fish, please consider quarantine first.> Shane <Cheers, J -- >

Skimmer and UV Thanks for the advice, I will buy the Remora hang-on, I will just have to buy the pump locally because of the different voltage and frequency. Another question: I intend to buy an UV-Sterilizer and I have seen recently the Tetratec UV-Sterilizer with a good price. Please find in the address below its specifications. http://www.shopsolution.nl/shop/home.asp?shopid=seameec&deptid=tetratechniek My aquarium is 230 liters. Do you think it is a good choice? Most display aquariums do not need a UV. They are better employed on the quarantine tank> Is it better to connect it as a by-pass on my external bio filter or to use a separate pump for it? <either way it needs slow flow and very well prefiltered water (chemically and mechanically treated). Anthony>

Re: ecosystem 60 and UV sterilizer I am getting conflicting thoughts from two local pet stores.  A small well run local store says it's ok to run an ecosystem 60 and a UV sterilizer together in series for filtration.  A local chain says that you absolutely never want to run a UV sterilizer period.  Unless there is something wrong in your tank.  He says that unless there is a presence of disease or a problem, a UV sterilizer should not be used.<They're nuts!> I need a professional impartial opinion.<Your about to get one!> I currently have a 55 gallon saltwater tank that I'm looking to setup more professionally to get better filtration.  I'm currently running a "Skilter" which is a mechanical filter and protein skimmer device.  It was relatively cheap and when I got started 5 years ago it was an economical decision.  I have probably 10lbs of live rock and only a few fish presently but before I add more I want to just get a better setup going. It's my understanding the EcoSystem 60 will significantly reduce the need for water changes and provide better overall filtration. Your response will be greatly appreciated. Thank you, Jeff Longmore <Jeff, let me start off saying that a U.V sterilizer can be used in a tank no problem.  But don't think it will solve all sickness problems etc. etc. it will help.  I must say though, you should look at updating your skimmer before adding a U.V sterilizer!  I've use Skilters and find them "iffy" at best.  A good skimmer would be much better!  A good skimmer should produce dark skimmate almost everyday!  The EcoSystem 60 will help with water changes to a point, but it's still up to you to do monthly or bi-monthly changes!  Go to www.wetwebmedia.com/marphysf.htm for more reading!  Hope this helps!  Phil>

Re: ecosystem 60 and UV sterilizer Wow!  Thank you for your prompt response!<No problem> I'm about to check out the link but as usual I have more thoughts and questions. Is the UV Sterilizer something that should/could be left on all the time?<You could leave it on all the time!  But it may not be needed> Could you recommend a quality skimmer for my 55 gallon tank.  Does the skimmer run all the time?<I run all my skimmers all the time!  I like Aqua-C, it would be great in a tank your size.> Unfortunately, I'm not terribly familiar with how a better setup like this should operate.  I know I want to improve the overall way my tank runs and is filtered to make it as low maintenance as possible.  I figure I'm willing to sink as much as $1K into it.  If there are more natural things I should be doing, like adding more live rock or plants or something I'd like to know so I can enjoy the hobby more. Thank you again, Jeff <Your best bet is to add more live rock, but not too much as this is not a reef tank.  I would say add another 10-15 pounds over the next few months, be sure to qt this rock!!!  Get a skimmer as I said before.  You don't need a U.V sterilizer really... if you want one, get it... I don't run them on my tanks.  Only on my pond.  What type of filter are you running, that plays a big factor in water filtration!  What kinda sand bed do you have?  That also plays a part!  E-mail me back w/ more spec's of the tank and what's in it and what will be going in it!  The more I know the better!  And this will not cost $1k if you do it right!!  Phil>  

Ich, UV, set-up Guys! How are you?? I am really grateful that people like you guys are here to help us newbie!!   <Glad to be here> Well, I am still fighting ich with a losing battle. I have been fighting this outbreak for 2 weeks now… I bought a Aquanetics UV sterilizer 25W last week. And I am not sure what I am doing is right. The way I hook it up is like this, the water going into the UV by using a tee junction with a switch (to control flow rate 200-300 gph ) from the sump pump (so water is gone through all filtration steps.) and after these water pass through the U.V , it goes into the protein skimmer (I have a Turboflotor 1000 AquaMedic , it uses 2 pumps, and I hook the water outlet from the UV to the skimmer water inlet) PLS LOOK AT PICTURE.   Is this hook up ok?? Because I have a Rio 600 pump, and the skimmer works fine. If not, what should I correct?? <All the water should circulate through the UV (that is the discharge from the sump back to your tank), rather than part loop back through your UV> For ich, I tried the natural approach (cleaner shrimp, vitamins… water change) but no success,… the UV hope to reduce free parasite, fish in main display are fine, Moorish idol killed in Hospital tank, really sad… <Yikes... not an easy fish to keep period... and UV really only helps in early/not-so-virulent cases of ich... won't cure the problem here. Please see: http://www.wetwebmedia.com/UVFAQs.htm> I have no room for hospital tank to let my tank go fallow for 31 days, is it ok for me to just treat the fish for 14 days in HT?? <Not really the better route to go, but may be your only choice here... just fishes in your system? Do you have enough "spare" pre-made water around to do water changes? Test kits for ammonia, nitrite?>    I guess my question is, can the 33 gallon HT ( AquaClear 500 filter, 301 powerhead with filter, protein skimmer and heater and proper lighting.) house the following fishes for 31 days with more than 50% success?? All fish are in good health 2 X 1.25 inch regal tang 1X 3.5 inch rusty angel 1X fire goby 1X 3.5 inch crown trigger 2X clown 1X 5 inch shoal tang 1X 5.5 inch powder blue tang pls advise. Also, I bought the new UV because I believe that UV is better than a diatom filter for reducing parasitic ich, mainly due to 1, less moving parts , 2, more scientific   3, continuous operation is this view correct??? <Not IMO/E... a UV would be better hands down for aiding in preventing such problems... the Diatom better for aiding in eradication> Lastly, my display is a 125 gallon tank, is 25W adequate?? And the instruction said that a flow rate of 250 GPH are able to kill protozoa , is that mean ich?? <Yes... but this will only kill free-living (in the water) stages... not the ones on the fish, developing on the substrate...> Pls answer me ASAP!!! Thanks!! <The types and amounts of fishes you have listed are problematic... please go to WetWebMedia.com and put each of their common name in the Google Search tool at the bottom of the homepage and read/study... For the amount of money you have invested in livestock and gear, there is no reason you have not found room for a quarantine system, that now could/would be utilized as a treatment tank. I would get and use one post-haste... Your system has an entrenched Cryptocaryon infestation that the UV will not solve... Treating the main tank will only lead to more troubles than you currently have. Please read here:    http://www.wetwebmedia.com/parasittksfaqs.htm and the linked (at top, in blue) FAQs files beyond... formulate a plan, get the treatment tank going, move and treat your fishes there. Bob Fenner> NEWBIE Eric

Hope I did not waste my money Hi! I want to thank you guys for your website. It's nice to get some good consistent advice. <Thank you very much!> It seems like every time I listen to my LFS's I end up with more problems. <That is a shame. Perhaps look into another store in your area. Also, try to locate a local marine aquarium society. Here you can find many educated opinions on the local stores, expert advice from seasoned aquarists, and good friends.> And the result being that I have transferred lots of money, from my wallet to theirs without making much progress. <But on the other hand you are helping to keep the economy humming :)> In reading your FAQ's I have noticed that you don't seem to mention the use of the UV sterilizer for the control of the parasites that cause ICH. <Correct. They are too often misapplied when a proper quarantine tank and protocol is much more effective and cheaper, too.> I have recently set up a 300 gallon fish only with lots of live rock. My approach to controlling the parasite problem is: to maintain a SPG of 1.015, <Wow! Pretty low for liverock. I prefer to attempt to replicate an environment closer to nature.> use cleaner shrimp, <I am surprised your shrimp are surviving. I also don't put a lot of faith into the cheap box hydrometers we all use. Your 1.015 reading could be 1.012-1.018 in reality. Calcium deposits, banging them around, and other activities mess up the measurements.> a 1-1/2" French Angel (as a cleaner) and a 120 watt UV sterilizer. I have very good circulation, using a Iwaki MD100RLT. I get about 4 to 5 turns per hour though the UV. <Your UV gets that much water through it! As long as you are following the manufacturer's specifications for effective kill rates of protozoans, you should be ok.> Did I waste my money going with the UV or did I do a good thing?<I would not say you wasted your money, but do not let the UV lull you into a false sense of security and add unquarantined fish to the display. Also, be sure to keep track of all the maintenance (replacement lamps, cleaning the quartz sleeve, polishing the water to ensure maximum UV penetration through the water, etc.). UV's are very labor intensive.> Thank you, Rick <You are welcome. -Steven Pro>

UV Sterilizers In Reef Tanks Good day, Frank here. <Scott F. here this afternoon> Do you think that UV Sterilizers will help my reef tank in brown alga bloom and hair alga ? <Probably not. They are effective at reducing unicellular algae, but I think that nutrient export/reduction is the key to removing the algae that you mentioned> Although I had use phosphate remover and MH light been used. Is MH light cause more alga problem than fluorescent lamp (NO, HO, VHO)? <Well- it's really not the light, in and of itself. It's the light in conjunction with high levels of nutrients, such as phosphate, nitrate, silicate, etc.> As far I know is that UV will kill bad and good floating bacteria, (phytoplankton - food for coral) that by pass it. So for bacteria in liverock and live sand, the UV will not have opportunity to kill it. right? <That's my opinion, too> Algae is a floating type , so my tank will have less brown alga on my front tank and hair algae if  I use UV Sterilizers? <Again- I think it's more a function of nutrient reduction. You will not see as much "green water" in a UV-equipped tank, but I don't think that there will be a noticeable reduction in hair or brown algae... You should work on improving water quality through efficient protein skimming, water changes, using quality make-up water (RO/DI), and careful feeding> That means also if I use UV, I will have to feed my fish and coral more, if not their will suffer from floating food in the water. <Well, I don't know about them "suffering", but UV use can alter or reduce populations of natural plankton in aquariums> Hope my question not confusing you ... Thank you. <I hope that I was able to clarify some things for you. Good luck!>

UV Use Hi, I wrote a couple of weeks ago about a 300 gallon fish only tank that would not clear up (very Cloudy) Your recommendation was a UV sterilizer. It worked great. Now my question is how long do I keep it on the tank? <Indefinitely> I'm getting ready to add some live rock. Will this effect the rock or the algae growth on the rock? <Won't affect negatively> Should I remove the UV or let it run Its been running about two weeks.   Thanks Again for your help, Rob <Thank you for your query. More questions re these physical filtration devices can be found archived here: http://www.wetwebmedia.com/marphysf.htm and the linked, UV FAQs beyond. Bob Fenner>

UV sterilization and live plankton What if any effect does U.V sterilization have on the live plankton I put in my tank for my corals? <much, most or all of the plankton that passes through the unit will be killed depending on the flow through rate (and efficacy of the set-up). UV is not recommended on reef tanks. It should not be necessary for disease control with proper QT of all new animals, and it should not be needed to temper green water with adequate nutrient export mechanisms (skimming, water changes, etc). UV's are commonly mis-sold for disease control yet they fail regularly due to improper installation. They need a fine polishing mechanical prefilter on the inlet, tank water needs to have aggressive clarity control (weekly carbon or daily ozone), the contact chamber needs a very slow flow through and a monthly purge to reduce mulm and other built up organics, and the bulb needs to be changed approximately every six months. And even when all of this is done... it can only kill what flows through it. Many larval parasites settle to the substrate and can rise and attack fishes before being drawn into the UV. UV are best run on bare glass bottomed aquaria for this and other reasons. Best regards, Anthony>

Re: new reef tank issues Hello Craig. <Hi Steven,> I do not have a secondary tank to quarantine the damsels. Will a small U.V sterilizer work? I am told it will eliminate the ick, but will also damage good organisms.  <No. Will kill Ick in water column but cannot circulate all the water in all the various crevices and such...so Ick will remain as long as there is a fish host (which the UV can't cure either). You can purchase a pretty nice QT set-up for the price of an ineffective UV.>  How long should the light be on ?  <Your main should run for twelve hours, it has corals that need the light. You can keep a QT for fish bare and dark (with a few plastic plants and places to hide). Do scrap the UV idea, it won't eliminate Ick> Can I add corals such as brain, clams, torch, etc. with ick in the tank once it has completed cycling?  <The Ick will not affect any other aquarium inhabitants but fish. Please keep in mind that Ick could come in on corals and rock kept in systems housing fish, so are to be QT'ed too.>  The only residents in my tank now are some snails, a couple crabs, and some things (polypus I think) growing on the live rock. <No worries there.> If the tank is without the infected fish for 1 month, will that be the end of the ick life cycle in the tank? I appreciate your ongoing help. Steve. <That is the life cycle. There are some particularly "virulent" forms that may persist, but if you read the links to disease, you will realize that the month fallow should be spent improving the conditions that led to this spike of Ick in your marine environment. To prepare for returning fish perhaps you should look into some cleaner shrimp and gobies to get after any remaining stress related outbreaks. You can check them out at Aquaria.com, or any of the other livestock sponsors of WetWebMedia.com. Sure hope this helps! Craig>

UV Filtration I recently upgraded from a 55 to a 90 gallon aggressive tank with abundant live rock (125-150 lbs), live sand (30 lbs?) and a small, happy & healthy community of creatures.  I am using a Fluval 402 canister filter and will be upgrading from a Red Sea Prism to a AquaC Remora Pro H/O filter.  As I am fairly new to the hobby, I am quite happy keeping less exotic, hardy species, but of course I would like to practice the best husbandry possible.  <<Hi Thomas! Craig Watson here answering some of Bob's inquiries while he attends the MACNA conference in Fort Worth. Nice upgrade on the skimmer, you won't regret it.   Wise to progress as you learn!>> My question is this:  is the UV filter going to be useful for me?  My thinking is that it would stabilize the environment during the stocking phase, as I will be adding several fish in the next few weeks. Your responses to FAQs regarding UV filtration seem to suggest that its usefulness is limited and that it might actually remove useful microorganisms as well as potentially harmful ones.  It strikes me that this is similar to the use of antibiotics to treat human disorders, which leads me to wonder:  is it possible to use UV filtration in a limited way, i.e. not to leave it on the system permanently, but rather to employ it when needed?  For example, would it make sense to put my UV filter on the tank in anticipation of acclimating new creatures, then only leave it on until they've been fully assimilated into the community?  Also, would it be useful to keep the UV filter handy in case of unexpected problems arising?  If so, when would it be appropriate to deploy it? <<I personally do not use UV.   I, like Bob, think it has limited usefulness.  There are others that endorse it strongly and swear by it.   Each group has what could be defined as success. I don't see UV helping you when stocking.  I can't recommend strongly enough though, the use of a quarantine tank for all new inhabitants. You can read about quarantine on WWM. The biggest issue when stocking is not overstepping your bio-capacity and UV can't help you there.  No fish should be stocked until after a proper quarantine. There are situations where UV can be helpful, but these are usually situations best avoided by proper husbandry and care. UV is routinely used for infestations if ick, velvet and other parasites.  While it kills these organisms in the water column not all of the organisms make it to the UV for treatment before they attach to rock, tank or substrate to then find a host.  Quarantine and treatment resolves this before it becomes a problem. UV is also used for algae control which could be better accomplished with clean nutrient free source water, nutrient export, skimming, filtration and feeding the correct amounts and types of food. I personally wouldn't use UV on a constant basis or go out and buy one, but if I had it and I had one of the aforementioned issues it wouldn't be harmful to use it temporarily. If it's new in the box and you could return it, I would invest in a nice QT tank which you will need and use more than the UV. I hope this helps, Craig>>

Re: UV Filtration Craig, Thanks for the helpful comments!  I think I may return the UV filter, after all. I wonder if I might trouble you for some more advice?  I would like to simulate a dawn/day/dusk lighting cycle and it seems like the best way for me to accomplish this would be with two 24" tank-top fixtures, each containing two bulbs with separate power cords and controls.  I could get away with a single 48" fixture, but it would be less convenient for working in the tank.  Anyway, the only ones I've been able to find so far are by Custom Sealife and they are quite expensive.  Since my tank is not a reef set-up, I don't know that I need the very best in lighting.  Would you have any more reasonable alternatives to suggest? Appreciatively, Thomas <<Hi Thomas, How much do they want for the 24" fixtures? Do you want a dimming dawn/dusk display or do you just want the lights to come on and go off in stages? If you want a true dimming cycle you should look into an Ice Cap ballast with a dimmer.  This actually dims the fluorescent lights. You can see them at http://www.championlighting.com/ or Marine Depot http://www.marinedepot.com/ There are of course other retailers as well. If cost is an issue, and of course it is for most of us, then you can go with multiple fixtures or one fixture and timer(s) without the dimmer. A good place to look for something like the CSL would be AH supply at: http://ahsupply.com/ Hope this helps! Craig>>

Angels and UV sterilizers and Monkey crap After I added live rock to my tank, I have unable to keep any type of angel fish longer than two months. My LFS made the following comments to me today: "If you have live rock, angel fish will get coral reef disease and not last more than two months. The only way to keep them alive is to use a UV sterilizer." <that explanation from your LFS is not only the biggest pile of steaming monkey crap that I have heard in weeks, but also the most shameless yet creative sales strategy for selling UV sterilizers that I have ever heard of. Did they explain what it is in live rock that specifically kills angels after the magic 8-week time-elapse (they need to come up with a much better explanation than a mythical "coral Reef Disease" to temper their "Pinocchio Disorder") or how it is that angels in the wild survive while living on and in live rock?!?! Furthermore, what is it that the UV does to correct this?> I was able to keep a bi color angel alive for several years when I had only lace rock in the tank. So maybe he is right? <he couldn't be any more wrong with an honorable mention for being patently ignorant or patently fraudulent. Did it cross your mind that maybe the problem with your angels is the source (ahem...)> Also, won't the UV sterilizer kill some of the good micro whatever stuff in the tank? <not really... and it also does a rather poor job of killing parasites in display tanks too as evidenced by the sick angels purchased from this LFS...heehee.> Thanks for your time. <May I suggest that you be certain to QT all new fishes from a full 4 weeks and also consider that bicolor angles are rather difficult to keep to begin with and that most seen in the trade are stressed and or drug caught Philippine specimens. They only cost about $6 wholesale which is why some retailers like to keep selling this challenging species... tempting profits. I'd reconsider the species overall despite your previous success and I will say that live rock will be necessary to keep this fish more than 2 years in captivity with less fear/concern of death by dietary deficiency. Best regards, Anthony> 

Odd UV Dear Bob, <Steven Pro this morning.> I would like to purchase a Vecton 15 watt UV sterilizer. There is only one active supplier in the US and will not sell to private individuals <Who is he selling to?> and I cannot find anyone who will or can order this for me. Can you help me? <We at WWM do not sell anything other than articles and images. I would contact this vendor again and ask for whom he sells to. One of these places has to be a retailer. Otherwise, I would shop for another brand. If getting the unit is such a hassle, getting replacement lamps will be too.> Thank you, Mona <You are welcome. -Steven Pro>

Rainbow Lifegard 25 watt UV Sterilizer <<Greetings...>> I have been given conflicting information on this sterilizer (Rainbow Lifegard 25 Watt). I was wondering if you could give me your opinion -- I highly value it. I currently run this on a 100gallon saltwater aquarium. I am moving up to a 160 gallon tank and thus started wondering if my current sterilizer would be ok to run with it. The flow rate for this particular model is 750gph. When I called the place that I got it from they said it would be fine to run it up to a 180 gallon. However, another place that I talked to said this: "Maybe if used as an algae clarifier but it would be pretty useless against parasites and many bacteria. A flow rate of 750 gph with a 25 watt sterilizer will give you a zap dose less than 8,000 microwatts/sec/sq. cm. That won’t even kill E. coli bacteria. It will work for ponds as an algae clarifier but that’s not the intended use for an indoor aquarium." In your opinion, Dr. Fenner, <<Well, two things quickly, I'm not Bob, and he's not a doctor, though he might play one on TV ;-) >> is this person correct in his thinking? <<Quite... it's true. The item that determines whether a UV sterilizer will work or not is the period of time the item being sterilized is kept in front of the bulb. For a typical 25w UV, the flow rate you would need to kill water-borne parasites is roughly 150 gph. By running at such a low rate, there's just no practical way to get all the system water into the UV in such a way to get 100% sterilized water. Is a much misunderstood fact about UV, but sadly is usually not money well spent. Much better off adopting good quarantine practices and stopping problems there before the leak into your main displays.>> Am I running an inappropriate sterilizer for an aquarium in the first place? <<I would try to run without one at all.>> What should I do -- I'm so confused and don't really know enough about this to make a competent decision. Thanks for any help you can provide. I appreciate it greatly! Elizabeth K. Birdwell